The present invention is directed to a method and a composition for treating wounds in a mammal, preferably a person, wherein the composition is taken orally, i.e., ingested, in order to promote healing of such wounds. The composition provides a concentrated and complete source of protein in a palatable form. Consequently, the palatable nature of the composition encourages compliance with a regimen of ingestion by a person in need of such treatment.
In U.S. Pat. No. 4,025,650, and its divisional patents, U.S. Pat. No. 4,042,687, U.S. Pat. No. 4,042,688, and U.S. Pat. No. 4,053,589, A. M. Gans, et al. disclose a method and composition for preventing nutritional deficiency and preventing or treating various medical conditions, including body wastage during oncologic treatment of cancer, obesity, providing rapid body build-up, treatment of nutritional deficiency, particularly that associated with surgery, cardiac cachexia, diabetes, hypoglycemia, gastroenterology, skin conditions related to lipid, cell glycogen and keratin deficiencies, and alcoholism. The disclosure of these patents is incorporated herein by reference to the extent permitted.
Various methods have been proposed for the treatment of wounds; see for example, in U.S. Pat. No. 5,929,050, G. D. Petito, U.S. Pat. No. 5,733,884, A. Barbul et al., and U.S. Pat. No. 5,985,339, A. Kamarei. The disclosures of these patents are incorporated herein by reference to the extent permitted.
A review of the medical journal literature reporting on the relationship between pressure sores or decubitus ulcers and nutrition was undertaken by T. E. Finucane, J. Am. Geriatric Soc., 43(4): 447-51 (1995). Overall, the author of the review concluded that data about the relationship between malnutrition and pressure sores are incomplete and contradictory. Several studies reporting on possible factors that influence pressure wound formation and healing have been reported in the literature including reviews that have carefully considered these reports and tried to analyze their sometimes conflicting conclusions. In general, there is reported a general association between improved nutrition and reduced incidence and improved healing of pressure ulcers. However, the studies rely on the intake of dietary protein requiring digestion, and digestion can be affected by the overall health, well-being and the functionality of critical organs, including the liver and kidneys. In contrast, the supplemental use of enzymatically hydrolyzed collagen, fortified so as to provide all of the essential amino acids, in the form of “pre-digested” protein, has not been considered for its effect on wound healing.
Pressure ulcers are also known as bedsores or decubitus ulcers. The ulcerated area of skin and tissue becomes injured or broken down typically as a consequence of an extended period of uninterrupted pressure or other continuing assault to the skin. Typically, pressure sores develop when the skin and underlying tissue is squeezed between a bone and an external surface, such as a bed or chair. The most common places for pressure ulcers are over bony prominences, such as the elbow, heels, hips, tailbone, ankles, shoulders, back, and the back of the head. Generally, pressure ulcers occur when a person is in a sitting or lying position for too long without shifting his or her weight. Thus, while anyone confined to a chair or bed is at risk, it is more commonly observed in the elderly and infirm. Incontinence and decreased sensory perception, e.g., due to a stroke, also increase the likelihood of developing bedsores. The constant pressure against the skin squeezes the blood vessels that supply nutrients and oxygen to the skin and nearby tissue partially or completely closed, causing a decreased blood supply to the area. The absence or severe reduction of oxygen and nutrients, results in the death of the skin and, potentially, underlying tissues. Left untreated, nearby tissue begins to die, eventually resulting in an ulcer that can also affect the bone. Severe ulceration, i.e., resulting in an opening in the skin can provide an entry for secondary infections; in particularly severe cases decubitus ulcers can result in death.
Several factors have been identified that increase the risk for decubitus ulcers, including: age, elderly people are at higher risk; inability to move certain parts of the body without assistance, such as the result of spinal or brain injury, and neuromuscular disease; malnutrition; being bedridden or in a wheelchair; a chronic condition such as diabetes or an arterial disease that inhibits prevents proper blood flow and nutrition; incontinence resulting in moisture next to the skin for long periods of time causing skin irritation and breakdown; reduced skin strength; and mental disability due to a condition such as Alzheimer's disease, that reduces the ability of an individual to take proper care or seek appropriate treatment when an ulcer forms.
The standard care taken for prevention or treatment include: identifying individuals at high risk for pressure ulcers; frequently changing the position of immobile patients, e.g., at least every two hours to relieve pressure; using items that can help reduce pressure caused by bedsheets and wheelchairs, e.g., pillows, sheepskin, and foam padding, to relieve pressure, and the use of powdered lubricants, salves or skin creams; making sure patients eat healthy, well-balanced meals; encouraging daily exercise, including range-of-motion exercises for immobile patients; following good skin care and personal hygiene.
The National Pressure Ulcer Advisory Panel (NPUAP), and corresponding panels in other countries and regions, e.g., Europe, Australia, etc. provides a rating system for evaluating decubitus ulcers covering a range from Stage I, the earliest signs, to Stage IV, most advanced, as follows:
Stage I: Non-blanchable erythema of intact skin, i.e., a reddened area that does not turn white or lighten when pressed. Discoloration of the skin, warmth, edema, induration or hardness may also be used as indicators, particularly on individuals with darker skin.
Stage II: Partial thickness skin loss involving epidermis, dermis, or both. The ulcer is superficial and presents clinically as an abrasion, blister or shallow crater.
Stage III: Full thickness skin loss involving damage to or necrosis of subcutaneous tissue that may extend down to, but not through underlying fascia. The ulcer presents clinically as a deep crater with or without undermining of adjacent tissue.
Stage IV: Extensive destruction, tissue necrosis, or damage to muscle, bone, or supporting structures with or without full thickness skin loss. Undermining and sinus tracts may also be present.
Guidelines for patient assessment and treatment are also provided, including ensuring adequate dietary intake to prevent malnutrition to the extent that this is compatible with the individual's wishes or condition. A protocol for wound treatment is also summarized and includes the following elements (described in further detail on the European website):
Debridement, which is defined as the removal of devitalized tissue from a wound. Methods of debridement include surgical, enzymatic, autolytic, larvae or a combination.
Cleanse wounds as necessary with tap water or with water suitable for drinking or with saline.
Use a dressing that maintains a moist environment at the wound/dressing interface. Reduce the risk of infection and enhance wound healing by hand washing, wound cleansing and debridement.
Institute, where appropriate, systemic antibiotic therapy for patients with bacteraemia, sepsis, advancing cellulitis or osteomyelitis. Systemic antibiotics are not required for pressure ulcers that exhibit only clinical signs of local infection.
As noted, evaluation of nutritional status is generally considered, as well as a general recommendation such as eating a balanced diet and, if that is not possible, the use of dietary supplements. This is also referred to in an article by D. R. Revis, published at eMedicine.com, wherein it is suggested that dietary supplements, enteral or parenteral feedings may be useful to restore a positive nitrogen balance and a serum protein level of 6 mg per 100 mL or higher to facilitate wound healing.
Bariatric surgery refers to surgical procedures undertaken to relieve morbid obesity, typically defined as being more than 100 pounds above ideal body weight or having a body mass index of greater than 40 kg/m2, in patients unresponsive to non-surgical therapy for weight loss. Such procedures are divided into restrictive and malabsorptive types of operations. The operations most frequently performed include Roux-en-Y gastric bypass, vertical banded gastroplasty, biliopancreatic diversion and its variations, various gastric banding procedures and, in certain circumstances Silastic® ring gastroplasty. These procedures are also performed using minimally invasive and laparoscopic techniques. Naturally, following these surgeries, as with all others, external as well as internal wounds of varying degrees are present. However, bariatric surgery patients are also subject to severely restricted nutritional intake following the surgery. For example, the total daily caloric intake ranges from about 150 to about 300 calories based on three meals each having a volume of less than 2 cooked ounces. Additionally, patients are typically advised to avoid sugar and fat and to eat protein-dense foods. Immediately after surgery only liquids are consumed; subsequently, a combination of liquids and semi-solids is permitted and then, about three weeks after surgery, solid foods are introduced. Consequently, it can be seen that there is a particular need for promoting wound healing in patients undergoing bariatric surgery. The composition of the present invention, having a complete amino acid profile in combination with a high protein concentration and low calorie content, may be particularly suitable for the long-term maintenance of a bariatric patient.
While various protein supplements are commercially available including some with disclosed uses for providing nutritional support to patients with wounds, the need remains for a method of promoting wound healing based on an ingestible composition that provides the proper balance of amino acids and calories in a concentration that does not unduly burden the body with excess fluids and fats.